Refactor JavaScriptFrame::function() to return a JSFunction* and remove associated casts.

BUG=

Review URL: https://codereview.chromium.org/18404009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15638 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/compiler.cc

@@ -565,8 +565,7 @@ static Handle<SharedFunctionInfo> MakeFunctionInfo(CompilationInfo* info) {
     if (info->is_eval()) {
       StackTraceFrameIterator it(isolate);
       if (!it.done()) {
-        script->set_eval_from_shared(
-            JSFunction::cast(it.frame()->function())->shared());
+        script->set_eval_from_shared(it.frame()->function()->shared());
         Code* code = it.frame()->LookupCode();
         int offset = static_cast<int>(
             it.frame()->pc() - code->instruction_start());

src/debug.cc

@@ -965,7 +965,7 @@ Object* Debug::Break(Arguments args) {
 
   // Get the debug info (create it if it does not exist).
   Handle<SharedFunctionInfo> shared =
-      Handle<SharedFunctionInfo>(JSFunction::cast(frame->function())->shared());
+      Handle<SharedFunctionInfo>(frame->function()->shared());
   Handle<DebugInfo> debug_info = GetDebugInfo(shared);
 
   // Find the break point where execution has stopped.
@@ -1348,8 +1348,7 @@ void Debug::FloodHandlerWithOneShot() {
     JavaScriptFrame* frame = it.frame();
     if (frame->HasHandler()) {
       // Flood the function with the catch block with break points
-      JSFunction* function = JSFunction::cast(frame->function());
-      FloodWithOneShot(Handle<JSFunction>(function));
+      FloodWithOneShot(Handle<JSFunction>(frame->function()));
       return;
     }
   }
@@ -1415,13 +1414,13 @@ void Debug::PrepareStep(StepAction step_action, int step_count) {
     // breakpoints.
     frames_it.Advance();
     // Fill the function to return to with one-shot break points.
-    JSFunction* function = JSFunction::cast(frames_it.frame()->function());
+    JSFunction* function = frames_it.frame()->function();
     FloodWithOneShot(Handle<JSFunction>(function));
     return;
   }
 
   // Get the debug info (create it if it does not exist).
-  Handle<JSFunction> function(JSFunction::cast(frame->function()));
+  Handle<JSFunction> function(frame->function());
   Handle<SharedFunctionInfo> shared(function->shared());
   if (!EnsureDebugInfo(shared, function)) {
     // Return if ensuring debug info failed.
@@ -1486,15 +1485,14 @@ void Debug::PrepareStep(StepAction step_action, int step_count) {
       frames_it.Advance();
     }
     // Skip builtin functions on the stack.
-    while (!frames_it.done() &&
-           JSFunction::cast(frames_it.frame()->function())->IsBuiltin()) {
+    while (!frames_it.done() && frames_it.frame()->function()->IsBuiltin()) {
       frames_it.Advance();
     }
     // Step out: If there is a JavaScript caller frame, we need to
     // flood it with breakpoints.
     if (!frames_it.done()) {
       // Fill the function to return to with one-shot break points.
-      JSFunction* function = JSFunction::cast(frames_it.frame()->function());
+      JSFunction* function = frames_it.frame()->function();
       FloodWithOneShot(Handle<JSFunction>(function));
       // Set target frame pointer.
       ActivateStepOut(frames_it.frame());
@@ -1916,7 +1914,7 @@ static void CollectActiveFunctionsFromThread(
         function->shared()->code()->set_gc_metadata(active_code_marker);
       }
     } else if (frame->function()->IsJSFunction()) {
-      JSFunction* function = JSFunction::cast(frame->function());
+      JSFunction* function = frame->function();
       ASSERT(frame->LookupCode()->kind() == Code::FUNCTION);
       active_functions->Add(Handle<JSFunction>(function));
       function->shared()->code()->set_gc_metadata(active_code_marker);
@@ -1933,7 +1931,7 @@ static void RedirectActivationsToRecompiledCodeOnThread(
 
     if (frame->is_optimized() || !frame->function()->IsJSFunction()) continue;
 
-    JSFunction* function = JSFunction::cast(frame->function());
+    JSFunction* function = frame->function();
 
     ASSERT(frame->LookupCode()->kind() == Code::FUNCTION);
 

src/deoptimizer.cc

@@ -186,7 +186,7 @@ DeoptimizedFrameInfo* Deoptimizer::DebuggerInspectableFrame(
   ASSERT(isolate->deoptimizer_data()->deoptimized_frame_info_ == NULL);
 
   // Get the function and code from the frame.
-  JSFunction* function = JSFunction::cast(frame->function());
+  JSFunction* function = frame->function();
   Code* code = frame->LookupCode();
 
   // Locate the deoptimization point in the code. As we are at a call the
@@ -1609,7 +1609,7 @@ void Deoptimizer::MaterializeHeapObjects(JavaScriptFrameIterator* it) {
   for (int frame_index = 0; frame_index < jsframe_count(); ++frame_index) {
     if (frame_index != 0) it->Advance();
     JavaScriptFrame* frame = it->frame();
-    Handle<JSFunction> function(JSFunction::cast(frame->function()), isolate_);
+    Handle<JSFunction> function(frame->function(), isolate_);
     Handle<JSObject> arguments;
     for (int i = frame->ComputeExpressionsCount() - 1; i >= 0; --i) {
       if (frame->GetExpression(i) == isolate_->heap()->arguments_marker()) {

src/frames-inl.h

@@ -274,10 +274,8 @@ inline bool JavaScriptFrame::has_adapted_arguments() const {
 }
 
 
-inline Object* JavaScriptFrame::function() const {
-  Object* result = function_slot_object();
-  ASSERT(result->IsJSFunction());
-  return result;
+inline JSFunction* JavaScriptFrame::function() const {
+  return JSFunction::cast(function_slot_object());
 }
 
 

src/frames.cc

@@ -205,7 +205,7 @@ void StackTraceFrameIterator::Advance() {
 
 bool StackTraceFrameIterator::IsValidFrame() {
     if (!frame()->function()->IsJSFunction()) return false;
-    Object* script = JSFunction::cast(frame()->function())->shared()->script();
+    Object* script = frame()->function()->shared()->script();
     // Don't show functions from native scripts to user.
     return (script->IsScript() &&
             Script::TYPE_NATIVE != Script::cast(script)->type()->value());
@@ -724,8 +724,7 @@ int JavaScriptFrame::GetArgumentsLength() const {
 
 
 Code* JavaScriptFrame::unchecked_code() const {
-  JSFunction* function = JSFunction::cast(this->function());
-  return function->code();
+  return function()->code();
 }
 
 
@@ -733,8 +732,7 @@ int JavaScriptFrame::GetNumberOfIncomingArguments() const {
   ASSERT(can_access_heap_objects() &&
          isolate()->heap()->gc_state() == Heap::NOT_IN_GC);
 
-  JSFunction* function = JSFunction::cast(this->function());
-  return function->shared()->formal_parameter_count();
+  return function()->shared()->formal_parameter_count();
 }
 
 
@@ -745,7 +743,7 @@ Address JavaScriptFrame::GetCallerStackPointer() const {
 
 void JavaScriptFrame::GetFunctions(List<JSFunction*>* functions) {
   ASSERT(functions->length() == 0);
-  functions->Add(JSFunction::cast(function()));
+  functions->Add(function());
 }
 
 
@@ -754,7 +752,7 @@ void JavaScriptFrame::Summarize(List<FrameSummary>* functions) {
   Code* code_pointer = LookupCode();
   int offset = static_cast<int>(pc() - code_pointer->address());
   FrameSummary summary(receiver(),
-                       JSFunction::cast(function()),
+                       function(),
                        code_pointer,
                        offset,
                        IsConstructor());
@@ -775,40 +773,35 @@ void JavaScriptFrame::PrintTop(Isolate* isolate,
       JavaScriptFrame* frame = it.frame();
       if (frame->IsConstructor()) PrintF(file, "new ");
       // function name
-      Object* maybe_fun = frame->function();
-      if (maybe_fun->IsJSFunction()) {
-        JSFunction* fun = JSFunction::cast(maybe_fun);
-        fun->PrintName();
-        Code* js_code = frame->unchecked_code();
-        Address pc = frame->pc();
-        int code_offset =
-            static_cast<int>(pc - js_code->instruction_start());
-        PrintF("+%d", code_offset);
-        SharedFunctionInfo* shared = fun->shared();
-        if (print_line_number) {
-          Code* code = Code::cast(
-              v8::internal::Isolate::Current()->heap()->FindCodeObject(pc));
-          int source_pos = code->SourcePosition(pc);
-          Object* maybe_script = shared->script();
-          if (maybe_script->IsScript()) {
-            Handle<Script> script(Script::cast(maybe_script));
-            int line = GetScriptLineNumberSafe(script, source_pos) + 1;
-            Object* script_name_raw = script->name();
-            if (script_name_raw->IsString()) {
-              String* script_name = String::cast(script->name());
-              SmartArrayPointer<char> c_script_name =
-                  script_name->ToCString(DISALLOW_NULLS,
-                                         ROBUST_STRING_TRAVERSAL);
-              PrintF(file, " at %s:%d", *c_script_name, line);
-            } else {
-              PrintF(file, " at <unknown>:%d", line);
-            }
+      JSFunction* fun = frame->function();
+      fun->PrintName();
+      Code* js_code = frame->unchecked_code();
+      Address pc = frame->pc();
+      int code_offset =
+          static_cast<int>(pc - js_code->instruction_start());
+      PrintF("+%d", code_offset);
+      SharedFunctionInfo* shared = fun->shared();
+      if (print_line_number) {
+        Code* code = Code::cast(
+            v8::internal::Isolate::Current()->heap()->FindCodeObject(pc));
+        int source_pos = code->SourcePosition(pc);
+        Object* maybe_script = shared->script();
+        if (maybe_script->IsScript()) {
+          Handle<Script> script(Script::cast(maybe_script));
+          int line = GetScriptLineNumberSafe(script, source_pos) + 1;
+          Object* script_name_raw = script->name();
+          if (script_name_raw->IsString()) {
+            String* script_name = String::cast(script->name());
+            SmartArrayPointer<char> c_script_name =
+                script_name->ToCString(DISALLOW_NULLS,
+                                       ROBUST_STRING_TRAVERSAL);
+            PrintF(file, " at %s:%d", *c_script_name, line);
           } else {
-            PrintF(file, " at <unknown>:<unknown>");
+            PrintF(file, " at <unknown>:%d", line);
           }
+        } else {
+          PrintF(file, " at <unknown>:<unknown>");
         }
-      } else {
-        PrintF("<unknown>");
       }
 
       if (print_args) {
@@ -913,7 +906,7 @@ void FrameSummary::Print() {
 JSFunction* OptimizedFrame::LiteralAt(FixedArray* literal_array,
                                       int literal_id) {
   if (literal_id == Translation::kSelfLiteralId) {
-    return JSFunction::cast(function());
+    return function();
   }
 
   return JSFunction::cast(literal_array->get(literal_id));
@@ -1018,7 +1011,7 @@ DeoptimizationInputData* OptimizedFrame::GetDeoptimizationData(
     int* deopt_index) {
   ASSERT(is_optimized());
 
-  JSFunction* opt_function = JSFunction::cast(function());
+  JSFunction* opt_function = function();
   Code* code = opt_function->code();
 
   // The code object may have been replaced by lazy deoptimization. Fall
@@ -1132,7 +1125,7 @@ void JavaScriptFrame::Print(StringStream* accumulator,
                             int index) const {
   HandleScope scope(isolate());
   Object* receiver = this->receiver();
-  Object* function = this->function();
+  JSFunction* function = this->function();
 
   accumulator->PrintSecurityTokenIfChanged(function);
   PrintIndex(accumulator, mode, index);
@@ -1146,29 +1139,27 @@ void JavaScriptFrame::Print(StringStream* accumulator,
   // or context slots.
   Handle<ScopeInfo> scope_info(ScopeInfo::Empty(isolate()));
 
-  if (function->IsJSFunction()) {
-    Handle<SharedFunctionInfo> shared(JSFunction::cast(function)->shared());
-    scope_info = Handle<ScopeInfo>(shared->scope_info());
-    Object* script_obj = shared->script();
-    if (script_obj->IsScript()) {
-      Handle<Script> script(Script::cast(script_obj));
-      accumulator->Add(" [");
-      accumulator->PrintName(script->name());
-
-      Address pc = this->pc();
-      if (code != NULL && code->kind() == Code::FUNCTION &&
-          pc >= code->instruction_start() && pc < code->instruction_end()) {
-        int source_pos = code->SourcePosition(pc);
-        int line = GetScriptLineNumberSafe(script, source_pos) + 1;
-        accumulator->Add(":%d", line);
-      } else {
-        int function_start_pos = shared->start_position();
-        int line = GetScriptLineNumberSafe(script, function_start_pos) + 1;
-        accumulator->Add(":~%d", line);
-      }
-
-      accumulator->Add("] ");
+  Handle<SharedFunctionInfo> shared(function->shared());
+  scope_info = Handle<ScopeInfo>(shared->scope_info());
+  Object* script_obj = shared->script();
+  if (script_obj->IsScript()) {
+    Handle<Script> script(Script::cast(script_obj));
+    accumulator->Add(" [");
+    accumulator->PrintName(script->name());
+
+    Address pc = this->pc();
+    if (code != NULL && code->kind() == Code::FUNCTION &&
+        pc >= code->instruction_start() && pc < code->instruction_end()) {
+      int source_pos = code->SourcePosition(pc);
+      int line = GetScriptLineNumberSafe(script, source_pos) + 1;
+      accumulator->Add(":%d", line);
+    } else {
+      int function_start_pos = shared->start_position();
+      int line = GetScriptLineNumberSafe(script, function_start_pos) + 1;
+      accumulator->Add(":~%d", line);
     }
+
+    accumulator->Add("] ");
   }
 
   accumulator->Add("(this=%o", receiver);
@@ -1258,7 +1249,7 @@ void JavaScriptFrame::Print(StringStream* accumulator,
 
   // Print details about the function.
   if (FLAG_max_stack_trace_source_length != 0 && code != NULL) {
-    SharedFunctionInfo* shared = JSFunction::cast(function)->shared();
+    SharedFunctionInfo* shared = function->shared();
     accumulator->Add("--------- s o u r c e   c o d e ---------\n");
     shared->SourceCodePrint(accumulator, FLAG_max_stack_trace_source_length);
     accumulator->Add("\n-----------------------------------------\n");
@@ -1273,10 +1264,8 @@ void ArgumentsAdaptorFrame::Print(StringStream* accumulator,
                                   int index) const {
   int actual = ComputeParametersCount();
   int expected = -1;
-  Object* function = this->function();
-  if (function->IsJSFunction()) {
-    expected = JSFunction::cast(function)->shared()->formal_parameter_count();
-  }
+  JSFunction* function = this->function();
+  expected = function->shared()->formal_parameter_count();
 
   PrintIndex(accumulator, mode, index);
   accumulator->Add("arguments adaptor frame: %d->%d", actual, expected);

src/frames.h

@@ -543,7 +543,7 @@ class JavaScriptFrame: public StandardFrame {
   virtual Type type() const { return JAVA_SCRIPT; }
 
   // Accessors.
-  inline Object* function() const;
+  inline JSFunction* function() const;
   inline Object* receiver() const;
   inline void set_receiver(Object* value);
 

src/ic.cc

@@ -159,7 +159,7 @@ Address IC::OriginalCodeAddress() const {
   JavaScriptFrame* frame = JavaScriptFrame::cast(it.frame());
   // Find the function on the stack and both the active code for the
   // function and the original code.
-  JSFunction* function = JSFunction::cast(frame->function());
+  JSFunction* function = frame->function();
   Handle<SharedFunctionInfo> shared(function->shared(), isolate());
   Code* code = shared->code();
   ASSERT(Debug::HasDebugInfo(shared));

src/isolate.cc

@@ -622,10 +622,8 @@ static bool IsVisibleInStackTrace(StackFrame* raw_frame,
   // Only display JS frames.
   if (!raw_frame->is_java_script()) return false;
   JavaScriptFrame* frame = JavaScriptFrame::cast(raw_frame);
-  Object* raw_fun = frame->function();
-  // Not sure when this can happen but skip it just in case.
-  if (!raw_fun->IsJSFunction()) return false;
-  if ((raw_fun == caller) && !(*seen_caller)) {
+  JSFunction* fun = frame->function();
+  if ((fun == caller) && !(*seen_caller)) {
     *seen_caller = true;
     return false;
   }
@@ -637,7 +635,6 @@ static bool IsVisibleInStackTrace(StackFrame* raw_frame,
   // The --builtins-in-stack-traces command line flag allows including
   // internal call sites in the stack trace for debugging purposes.
   if (!FLAG_builtins_in_stack_traces) {
-    JSFunction* fun = JSFunction::cast(raw_fun);
     if (frame->receiver()->IsJSBuiltinsObject() ||
         (fun->IsBuiltin() && !fun->shared()->native())) {
       return false;
@@ -1201,7 +1198,7 @@ void Isolate::PrintCurrentStackTrace(FILE* out) {
     int pos = frame->LookupCode()->SourcePosition(frame->pc());
     Handle<Object> pos_obj(Smi::FromInt(pos), this);
     // Fetch function and receiver.
-    Handle<JSFunction> fun(JSFunction::cast(frame->function()));
+    Handle<JSFunction> fun(frame->function());
     Handle<Object> recv(frame->receiver(), this);
     // Advance to the next JavaScript frame and determine if the
     // current frame is the top-level frame.
@@ -1225,7 +1222,7 @@ void Isolate::ComputeLocation(MessageLocation* target) {
   StackTraceFrameIterator it(this);
   if (!it.done()) {
     JavaScriptFrame* frame = it.frame();
-    JSFunction* fun = JSFunction::cast(frame->function());
+    JSFunction* fun = frame->function();
     Object* script = fun->shared()->script();
     if (script->IsScript() &&
         !(Script::cast(script)->source()->IsUndefined())) {

src/liveedit.cc

@@ -1621,8 +1621,7 @@ static bool CheckActivation(Handle<JSArray> shared_info_array,
                             LiveEdit::FunctionPatchabilityStatus status) {
   if (!frame->is_java_script()) return false;
 
-  Handle<JSFunction> function(
-      JSFunction::cast(JavaScriptFrame::cast(frame)->function()));
+  Handle<JSFunction> function(JavaScriptFrame::cast(frame)->function());
 
   Isolate* isolate = shared_info_array->GetIsolate();
   int len = GetArrayLength(shared_info_array);

src/runtime-profiler.cc

@@ -247,7 +247,7 @@ void RuntimeProfiler::OptimizeNow() {
        frame_count++ < frame_count_limit && !it.done();
        it.Advance()) {
     JavaScriptFrame* frame = it.frame();
-    JSFunction* function = JSFunction::cast(frame->function());
+    JSFunction* function = frame->function();
 
     if (!FLAG_watch_ic_patching) {
       // Adjust threshold each time we have processed

src/runtime.cc

@@ -2797,7 +2797,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateJSGeneratorObject) {
 
   JavaScriptFrameIterator it(isolate);
   JavaScriptFrame* frame = it.frame();
-  JSFunction* function = JSFunction::cast(frame->function());
+  JSFunction* function = frame->function();
   RUNTIME_ASSERT(function->shared()->is_generator());
 
   JSGeneratorObject* generator;
@@ -2826,8 +2826,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_SuspendJSGeneratorObject) {
 
   JavaScriptFrameIterator stack_iterator(isolate);
   JavaScriptFrame* frame = stack_iterator.frame();
-  RUNTIME_ASSERT(JSFunction::cast(frame->function())->shared()->is_generator());
-  ASSERT_EQ(JSFunction::cast(frame->function()), generator_object->function());
+  RUNTIME_ASSERT(frame->function()->shared()->is_generator());
+  ASSERT_EQ(frame->function(), generator_object->function());
 
   // The caller should have saved the context and continuation already.
   ASSERT_EQ(generator_object->context(), Context::cast(frame->context()));
@@ -5732,9 +5732,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_GetArgumentsProperty) {
   // Handle special arguments properties.
   if (key->Equals(isolate->heap()->length_string())) return Smi::FromInt(n);
   if (key->Equals(isolate->heap()->callee_string())) {
-    Object* function = frame->function();
-    if (function->IsJSFunction() &&
-        !JSFunction::cast(function)->shared()->is_classic_mode()) {
+    JSFunction* function = frame->function();
+    if (!function->shared()->is_classic_mode()) {
       return isolate->Throw(*isolate->factory()->NewTypeError(
           "strict_arguments_callee", HandleVector<Object>(NULL, 0)));
     }
@@ -8221,7 +8220,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_NotifyDeoptimized) {
 
   JavaScriptFrame* frame = it.frame();
   RUNTIME_ASSERT(frame->function()->IsJSFunction());
-  Handle<JSFunction> function(JSFunction::cast(frame->function()), isolate);
+  Handle<JSFunction> function(frame->function(), isolate);
   Handle<Code> optimized_code(function->code());
   RUNTIME_ASSERT((type != Deoptimizer::EAGER &&
                   type != Deoptimizer::SOFT) || function->IsOptimized());
@@ -8237,7 +8236,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_NotifyDeoptimized) {
   bool has_other_activations = false;
   while (!it.done()) {
     JavaScriptFrame* frame = it.frame();
-    JSFunction* other_function = JSFunction::cast(frame->function());
+    JSFunction* other_function = frame->function();
     if (frame->is_optimized() && other_function->code() == function->code()) {
       has_other_activations = true;
       break;
@@ -8353,8 +8352,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_NeverOptimize) {
     // Disable optimization for the calling function.
     JavaScriptFrameIterator it(isolate);
     if (!it.done()) {
-      JSFunction *function = JSFunction::cast(it.frame()->function());
-      function->shared()->set_optimization_disabled(true);
+      it.frame()->function()->shared()->set_optimization_disabled(true);
     }
     return isolate->heap()->undefined_value();
   }
@@ -11235,7 +11233,7 @@ static bool SetLocalVariableValue(Isolate* isolate,
     return false;
   }
 
-  Handle<JSFunction> function(JSFunction::cast(frame->function()));
+  Handle<JSFunction> function(frame->function());
   Handle<SharedFunctionInfo> shared(function->shared());
   Handle<ScopeInfo> scope_info(shared->scope_info());
 
@@ -11482,7 +11480,7 @@ class ScopeIterator {
     : isolate_(isolate),
       frame_(frame),
       inlined_jsframe_index_(inlined_jsframe_index),
-      function_(JSFunction::cast(frame->function())),
+      function_(frame->function()),
       context_(Context::cast(frame->context())),
       nested_scope_chain_(4),
       failed_(false) {
@@ -11863,7 +11861,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_GetStepInPositions) {
   JavaScriptFrame* frame = frame_it.frame();
 
   Handle<SharedFunctionInfo> shared =
-      Handle<SharedFunctionInfo>(JSFunction::cast(frame->function())->shared());
+      Handle<SharedFunctionInfo>(frame->function()->shared());
   Handle<DebugInfo> debug_info = Debug::GetDebugInfo(shared);
 
   int len = 0;